CCAMP Working Group                                              Y. Lee
Internet Draft                                                 H. Zheng
Intended status: Standard Track                                  Huawei
Expires: March 1, 2019


                                                        August 31, 2018

       A Yang Data Model for Impairment-Aware WSON Optical Networks


                  draft-lee-ccamp-wson-impairment-yang-00


Abstract

   This document provides a YANG data model for the impairment-aware TE
   topology in wavelength switched optical networks (WSONs).



Status of this Memo

   This Internet-Draft is submitted to IETF in full conformance with
   the provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
   other groups may also distribute working documents as Internet-
   Drafts.

   Internet-Drafts are draft documents valid for a maximum of six
   months and may be updated, replaced, or obsoleted by other documents
   at any time.  It is inappropriate to use Internet-Drafts as
   reference material or to cite them other than as "work in progress."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html

   This Internet-Draft will expire on March 1, 2019.

Copyright Notice



   Copyright (c) 2018 IETF Trust and the persons identified as the
   document authors.  All rights reserved.



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   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document. Please review these documents
   carefully, as they describe your rights and restrictions with
   respect to this document.  Code Components extracted from this
   document must include Simplified BSD License text as described in
   Section 4.e of the Trust Legal Provisions and are provided without
   warranty as described in the Simplified BSD License.

Table of Contents


   1. Introduction...................................................2
      1.1. Terminology...............................................3
      1.2. Tree diagram..............................................3
      1.3. Prefixes in Data Node Names...............................4
   2. YANG Model (Tree Structure)....................................4
   3. IETF-WSON-Topology YANG Model..................................6
   4. Security Considerations.......................................16
   5. IANA Considerations...........................................16
   6. Acknowledgments...............................................16
   7. References....................................................17
      7.1. Normative References.....................................17
      7.2. Informative References...................................17
   8. Contributors..................................................18
   Authors' Addresses...............................................18

1. Introduction

   In order to provision an optical connection (an optical path)
   through a WSON, a combination of path continuity, resource
   availability, and impairment constraints must be met to determine
   viable and optimal paths through the network.  The determination of
   appropriate paths is known as Impairment-Aware Routing and
   Wavelength Assignment (IA-RWA) [RFC6566].

   This document provides a YANG data model for the impairment-aware
   Traffic Engineering (TE) topology in wavelength switched optical
   networks (WSONs). The YANG model described in this document is a
   WSON technology-specific Yang model based on the information model
   developed in [RFC7446] and the two encoding documents [RFC7581] and
   [RFC7579] that developed protocol independent encodings based on
   [RFC7446].

   The intent of this document is to provide a Yang data model, which
   can be utilized by an MDSC to collect states of WSON impairment data


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   from the Transport PNCs to enable impairment-aware optical path
   computation according to the ACTN Architecture [RFC8453]. The
   communication between controllers is done via a NETCONF [RFC8341].

   This document augments the generic TE topology draft [TE-TOPO] and
   reuses groupings via importing other modules such as ietf-wson-
   topology and ietf-te-wson-types defined in [WSON-TOPO].

   This document defines one YANG module: ietf-wson-impairment-topology
   (Section 3) according to the new Network Management Datastore
   Architecture [RFC8342].

1.1. Terminology

   Refer to [RFC4847] and [RFC5253] for the key terms used in this
   document.

   The following terms are defined in [RFC7950] and are not redefined
   here:

   o client

   o server

   o augment

   o data model

   o data node

   The following terms are defined in [RFC6241] and are not redefined
   here:

   o  configuration data

   o  state data

   The terminology for describing YANG data models is found in
   [RFC7950].

1.2. Tree diagram

   A simplified graphical representation of the data model is used in
   Section 2 of this this document.  The meaning of the symbols in
   these diagrams is defined in [RFC8340].




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1.3. Prefixes in Data Node Names

   In this document, names of data nodes and other data model objects
   are prefixed using the standard prefix associated with the
   corresponding YANG imported modules, as shown in Table 1.

      +---------------+-------------------------------+------------+
      | Prefix        | YANG module                   | Reference  |
      +---------------+-------------------------------+------------+
      | wson-imp-topo | ietf-wson-impairment-topology | [RFC XXXX] |
      +---------------+-------------------------------+------------+

             Table 1: Prefixes and corresponding YANG modules

   Note: The RFC Editor will replace XXXX with the number assigned to
   the RFC once this draft becomes an RFC.



2. YANG Model (Tree Structure)



   module: ietf-wson-impairment-topology
     augment /nw:networks/nw:network/nw:network-types/tet:te-topology:
       +--rw wson-impairment-topology!
     augment /nw:networks/nw:network/nt:link/tet:te/tet:te-link-attributes:
       +--ro power?   int32
     augment /nw:networks/nw:network/nt:link/tet:te/tet:te-link-
   attributes/tet:underlay/tet:primary-path/tet:path-
   element/tet:type/tet:label/tet:label-hop/tet:te-label/tet:technology:
       +--:(wson-imp-topo)
          +--rw (grid-type)?
          |  +--:(dwdm)
          |  |  +--ro channel-freq?         decimal64
          |  +--:(cwdm)
          |     +--ro channel-wavelength?   uint32
          +--ro bit-rate?             decimal64
          +--ro BER?                  decimal64
          +--ro pmd?                  decimal64
          +--ro cd?                   decimal64
          +--ro osnr?                 decimal64
          +--ro q-factor?             decimal64
     augment /nw:networks/nw:network/nt:link/tet:te/tet:te-link-
   attributes/tet:underlay/tet:backup-path/tet:path-
   element/tet:type/tet:label/tet:label-hop/tet:te-label/tet:technology:
       +--:(wson-imp-topo)
          +--rw (grid-type)?


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          |  +--:(dwdm)
          |  |  +--ro channel-freq?         decimal64
          |  +--:(cwdm)
          |     +--ro channel-wavelength?   uint32
          +--ro bit-rate?             decimal64
          +--ro BER?                  decimal64
          +--ro pmd?                  decimal64
          +--ro cd?                   decimal64
          +--ro osnr?                 decimal64
          +--ro q-factor?             decimal64
     augment /nw:networks/tet:te/tet:templates/tet:link-template/tet:te-link-
   attributes/tet:underlay/tet:primary-path/tet:path-
   element/tet:type/tet:label/tet:label-hop/tet:te-label/tet:technology:
       +--:(wson-imp-topo)
          +--rw (grid-type)?
          |  +--:(dwdm)
          |  |  +--ro channel-freq?         decimal64
          |  +--:(cwdm)
          |     +--ro channel-wavelength?   uint32
          +--ro bit-rate?             decimal64
          +--ro BER?                  decimal64
          +--ro pmd?                  decimal64
          +--ro cd?                   decimal64
          +--ro osnr?                 decimal64
          +--ro q-factor?             decimal64
     augment /nw:networks/tet:te/tet:templates/tet:link-template/tet:te-link-
   attributes/tet:underlay/tet:backup-path/tet:path-
   element/tet:type/tet:label/tet:label-hop/tet:te-label/tet:technology:
       +--:(wson-imp-topo)
          +--rw (grid-type)?
          |  +--:(dwdm)
          |  |  +--ro channel-freq?         decimal64
          |  +--:(cwdm)
          |     +--ro channel-wavelength?   uint32
          +--ro bit-rate?             decimal64
          +--ro BER?                  decimal64
          +--ro pmd?                  decimal64
          +--ro cd?                   decimal64
          +--ro osnr?                 decimal64
          +--ro q-factor?             decimal64
     augment /nw:networks/nw:network/nw:node/tet:te/tet:te-node-attributes:
       +--rw wson-node
          +--rw node-type?   identityref
     augment /nw:networks/nw:network/nw:node/tet:te/tet:tunnel-termination-point:
       +--ro available-modulation*   identityref
       +--ro modulation-enabled?     boolean
       +--ro modulation-type?        identityref
       +--ro available-FEC*          identityref
       +--ro FEC-enabled?            boolean



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       +--ro FEC-type?               identityref
       +--ro FEC-code-rate?          decimal64
       +--ro FEC-threshold?          decimal64
     augment /nw:networks/nw:network/nw:node/tet:te/tet:tunnel-termination-point:
       +--ro transponder-list* [carrier-id]
          +--ro carrier-id    uint32

3. IETF-WSON-Topology YANG Model


<CODE BEGINS> file "ietf-wson-impairment-topology@2018-08-31.yang"

module   ietf-wson-impairment-topology {
  yang-version 1.1;

  namespace "urn:ietf:params:xml:ns:yang:ietf-wson-impairment-topology";

  prefix "wson-imp-topo";

  import ietf-network {
    prefix "nw";
  }

  import ietf-network-topology {
    prefix "nt";
  }

  import ietf-te-topology {
    prefix "tet";
  }

  import ietf-wson-topology {
    prefix "wson";
  }

  import ietf-te-wson-types {
    prefix "te-wson-types";
  }

  organization
    "IETF CCAMP Working Group";

  contact
    "Editor:   Young Lee  <leeyoung@huawei.com>";

  description
   "This module contains a collection of YANG definitions for


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   Impairment-aware RWA WSON.

   Copyright (c) 2018 IETF Trust and the persons identified as
   authors of the code.  All rights reserved.

   Redistribution and use in source and binary forms, with or
   without modification, is permitted pursuant to, and subject
   to the license terms contained in, the Simplified BSD
   License set forth in Section 4.c of the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info).";

  revision 2018-08-31{
   description
      "version 0.";
      reference
        "RFC XXX: A Yang Data Model for Impairment-aware WSON Optical Networks ";
  }

  identity modulation {
    description "base identity for modulation type";
  }
  identity QPSK {
   base modulation;
   description
      "QPSK (Quadrature Phase Shift Keying) modulation";
  }
  identity DP_QPSK {
    base modulation;
    description
     "DP-QPSK (Dual Polarization Quadrature
      Phase Shift Keying) modulation";
  }
  identity QAM16 {
    base modulation;
   description
     "QAM16 (Quadrature Amplitude Modulation
      - 4 bits per symbol) modulation";
  }
  identity  DP_QAM16 {
    base modulation;
    description
     "DP-QAM16 (Dual Polarization Quadrature Amplitude Modulation
     - 4 bits per symbol) modulation";
  }
  identity DC_DP_QAM16 {
    base modulation;


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    description
     "DC DP-QAM16 (Dual Polarization Quadrature Amplitude Modulation
     - 4 bits per symbol) modulation";
  }


  identity FEC {
    description
     "Enumeration that defines the type of
      Forward Error Correction";
  }
  identity reed-solomon {
    base FEC;
   description
     "Reed-Solomon error correction";
  }
  identity hamming-code {
    base FEC;
   description
     "Hamming Code error correction";
  }
  identity golay {
    base FEC;
   description "Golay error correction";
  }


  grouping wson-label {
    description
      "Generic label for WSON links and paths";
    choice grid-type {
      description
        "Label for DWDM or CWDM grid";
      case dwdm {
        leaf channel-freq {
          type decimal64 {
            fraction-digits 5;
          }
          units THz;
        config false;
          description
            "The DWDM frequency in THz, e.g. 193.12500";
          reference
            "RFC6205";
        }
      }
      case cwdm {


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        leaf channel-wavelength {
          type uint32;
          units nm;
        config false;
          description
            "The CWDM wavelength in nanometer, e.g. 1511";
          reference
            "RFC6205";
        }
      }
    }
  }


  grouping transponder-attributes {
   description "Configuration of an optical transponder";
   leaf-list available-modulation {
      type identityref {
        base modulation;
      }
      config false;
      description
         "List determining all the available modulations";
   }
   leaf modulation-enabled {
      type boolean;
      config false;
      description
         "Determines whether the modulation is enabled or not";
   }
   leaf modulation-type {
      type identityref {
        base modulation;
      }
      config false;
      description
         "Modulation type of the transponder";
   }
   leaf-list available-FEC {
      type identityref {
        base FEC;
      }
      config false;
      description "List determining all the available FEC";
   }
   leaf FEC-enabled {
      type boolean;


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      config false;
      description
         "Determines whether the FEC is enabled or not";
   }
   leaf FEC-type {
      type identityref {
        base FEC;
      }
      config false;
      description
         "FEC type of the transponder";
   }
   leaf FEC-code-rate {
      type decimal64 {
        fraction-digits 8;
        range "0..max";
      }
      config false;
      description "FEC-code-rate";
   }
   leaf FEC-threshold {
      type decimal64 {
        fraction-digits 8;
        range "0..max";
      }
      config false;
      description "Threshold on the BER, for which FEC is able to correct errors";
   }
  }

  grouping sliceable-transponder-attributes {
   description
      "Configuration of a sliceable transponder.";
   list transponder-list {
      key "carrier-id";
      config false;
      description "List of carriers";
      leaf carrier-id {
         type uint32;
         config false;
         description "Identifier of the carrier";
      }
   }
  }

  grouping wson-node-attributes {
   description "WSON node attributes";


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   container wson-node {
      description "WSON node attrtibutes.";
      leaf node-type {
       type identityref {
         base te-wson-types:wson-node-type;
       }
       description "WSON node type.";
      }
   }
  }

  grouping wson-fiber-data {
   description "WSON link (fiber) attributes with impairment data";
     leaf power {
      type int32;
      units "dBm";
      config false;
      description "Input Power Level of the receiver side of the link";
      }
  }

  grouping wson-impairement-data {
   description "WSON impairment data per wavelength";
     leaf bit-rate {
       type decimal64 {
         fraction-digits 8;
         range "0..max";
       }
       units "Gbit/s";
      config false;
       description "Gross bit rate";
     }
     leaf BER {
       type decimal64 {
        fraction-digits 18;
          range "0..max";
        }
        config false;
        description "BER";
     }
     leaf pmd {
       type decimal64 {
        fraction-digits 8;
        range "0..max";
       }
       units "ps/(km)^0.5";
       config false;


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        description "Polarization Mode Dispersion";
     }
     leaf cd {
       type decimal64 {
        fraction-digits 5;
       }
       units "ps/nm/km";
       config false;
       description "Cromatic Dispersion";
     }
     leaf osnr {
       type decimal64 {
        fraction-digits 5;
       }
       units "dB";
       config false;
       description "osnr";
     }
     leaf q-factor {
       type decimal64 {
        fraction-digits 5;
       }
       units "dB";
       config false;
       description "q-factor";
     }
  }

  /*
  grouping wson-ttp-attributes {
    description
      "WSON tunnel termination point (e.g.tranponder) attributes";
      leaf-list available-operational-mode {
        type te-wson-types:operational-mode;
        description "List of all vendor-specific supported
        mode identifiers";
      }

      leaf operational-mode {
        type te-wson-types:operational-mode;
        description "Vendor-specific mode identifier";
      }
  }
  */

/* Data nodes */



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  augment "/nw:networks/nw:network/nw:network-types"
    + "/tet:te-topology" {
    description "wson-impairment topology augmented";
    container wson-impairment-topology {
      presence "indicates an impairment-aware topology of wson";
      description
       "Container to identify impairment-aware wson topology type";
    }
  }

  augment "/nw:networks/nw:network/nt:link/tet:te"
    + "/tet:te-link-attributes"   {
    when "/nw:networks/nw:network/nw:network-types"
      +"/tet:te-topology/wson-imp-topo:wson-impairment-topology" {
      description
        "This augment is only valid for WSON Impairment.";
    }
    description "WSON Link augmentation for impairment data.";
    uses wson-fiber-data;
  }

    /* Augment label hop of underlay primary path of TE link */
  augment "/nw:networks/nw:network/nt:link/tet:te/"
        + "tet:te-link-attributes/"
        + "tet:underlay/tet:primary-path/tet:path-element/tet:type/"
        + "tet:label/tet:label-hop/tet:te-label/tet:technology" {
    when "../../../../../../../../"
       + "nw:network-types/tet:te-topology/"
       + "wson:wson-topology" {
      description "Augment WSON TE label";
    }
    description "WSON label.";
    case wson-imp-topo {
      uses wson-label;
     uses wson-impairement-data;
    }
  }

  /* Augment label hop of underlay backup path of TE link */
  augment "/nw:networks/nw:network/nt:link/tet:te/"
        + "tet:te-link-attributes/"
        + "tet:underlay/tet:backup-path/tet:path-element/tet:type/"
        + "tet:label/tet:label-hop/tet:te-label/tet:technology" {
    when "../../../../../../../../"
       + "nw:network-types/tet:te-topology/"
       + "wson:wson-topology" {
      description "Augment WSON TE label";


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    }
    description "WSON label.";
    case wson-imp-topo {
      uses wson-label;
     uses wson-impairement-data;
    }
  }
    /* Augment label hop of underlay primary path of TE link template */
  augment "/nw:networks/tet:te/tet:templates/"
        + "tet:link-template/tet:te-link-attributes/"
        + "tet:underlay/tet:primary-path/tet:path-element/tet:type/"
        + "tet:label/tet:label-hop/tet:te-label/tet:technology" {
/*
    when "../../../../../../../../../"
       + "nw:network-types/tet:te-topology/"
       + "wson:wson-topology" {
          description "Augment WSON TE label";
    }
*/
    description "WSON label.";
    case wson-imp-topo {
      uses wson-label;
     uses wson-impairement-data;
    }
  }

  /* Augment label hop of underlay backup path of TE link template */
  augment "/nw:networks/tet:te/tet:templates/"
        + "tet:link-template/tet:te-link-attributes/"
        + "tet:underlay/tet:backup-path/tet:path-element/tet:type/"
        + "tet:label/tet:label-hop/tet:te-label/tet:technology" {
/*
    when "../../../../../../../../../"
       + "nw:network-types/tet:te-topology/"
       + "wson:wson-topology" {
      description "Augment WSON TE label";
    }
*/
    description "WSON label.";
    case wson-imp-topo {
      uses wson-label;
     uses wson-impairement-data;
    }
  }





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  augment "/nw:networks/nw:network/nw:node/tet:te"
    + "/tet:te-node-attributes" {
    when "/nw:networks/nw:network/nw:network-types"
      +"/tet:te-topology/wson:wson-topology" {
      description
        "This augment is only valid for WSON.";
    }
    description "WSON Node augmentation.";
    uses wson-node-attributes;
  }


  augment "/nw:networks/nw:network/nw:node/tet:te"
    + "/tet:tunnel-termination-point" {
    when "/nw:networks/nw:network/nw:network-types"
      +"/tet:te-topology/wson-imp-topo:wson-impairment-topology" {
      description
        "This augment is only valid for Impairment WSON with non-sliceable
        transponder model";
    }
    description
      "WSON tunnel termination point
      augmentation for non-sliceabletransponder model.";

   /* uses wson-ttp-attributes; */
    uses transponder-attributes;
  }

  augment "/nw:networks/nw:network/nw:node/tet:te"
    + "/tet:tunnel-termination-point" {
    when "/nw:networks/nw:network/nw:network-types"
      +"/tet:te-topology/wson-imp-topo:wson-impairment-topology" {
      description
        "This augment is only valid for Impairment WSON with sliceable
        transponder model";
    }
    description
      "WSON tunnel termination point augmentation for sliceabletransponder model.";
    uses sliceable-transponder-attributes;
  }
}
<CODE ENDS>





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4. Security Considerations

   The configuration, state, and action data defined in this document
   are designed to be accessed via a management protocol with a secure
   transport layer, such as NETCONF [RFC6241].  The NETCONF access
   control model [RFC6536] provides the means to restrict access for
   particular NETCONF users to a preconfigured subset of all available
   NETCONF protocol operations and content.

   A number of configuration data nodes defined in this document are
   read-only; however, these data nodes may be considered sensitive or
   vulnerable in some network environments.

5. IANA Considerations

   This document registers the following namespace URIs in the IETF XML
   registry [RFC3688]:



   --------------------------------------------------------------------
      URI: urn:ietf:params:xml:ns:yang:ietf-wson-impairment-topology
      Registrant Contact: The IESG.
      XML: N/A, the requested URI is an XML namespace.
   --------------------------------------------------------------------


   This document registers the following YANG modules in the YANG
   Module Names registry [RFC7950]:

   --------------------------------------------------------------------
   name:      ietf-wson-impairment-topology
   namespace: urn:ietf:params:xml:ns:yang:ietf-wson-impairment-
   topology

   reference: RFC XXXX (TDB)
   --------------------------------------------------------------------


6. Acknowledgments

   This document was prepared using 2-Word-v2.0.template.dot.




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7. References

   7.1. Normative References



   7.2. Informative References

   [RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
             and A. Bierman, Ed., "Network Configuration Protocol
             (NETCONF)", RFC 6241, June 2011.

   [RFC6566]  Y. Lee, G. Bernstein, D. Li, G. Martinelli, "A Framework
             for the Control of Wavelength Switched Optical Networks
             (WSONs) with Impairments", RFC 6566, March 2012.

   [RFC7446]  Y. Lee, G. Bernstein, D. Li, W. Imajuku, "Routing and
             Wavelength Assignment Information Model for Wavelength
             Switched Optical Networks", RFC 7446, Feburary 2015.

   [RFC7579]   G. Bernstein, Y. Lee, D. Li, W. Imajuku, "General
             Network Element Constraint Encoding for GMPLS Controlled
             Networks", RFC 7579, June 2015.

   [RFC7581]  G. Bernstein, Y. Lee, D. Li, W. Imajuku, "Routing and
             Wavelength Assignment Information Encoding for Wavelength
             Switched Optical Networks", RFC 7581, June 2015.

   [RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
             RFC 7950, August 2016.

   [RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration
             Access Control Model", RFC 8341, March 2018.

   [RFC8342]  Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
             and R. Wilton, "Network Management Datastore Architecture
             (NMDA)", RFC 8342, March 2018.

   [TE-TOPO] X. Liu, et al., "YANG Data Model for TE Topologies", work
             in progress: draft-ietf-teas-yang-te-topo.

   [RFC8453] Ceccarelli, D. and Y. Lee, "Framework for Abstraction and
             Control of Traffic Engineered Networks", RFC 8453, August
             2018.



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Internet-Draft     WSON Impairment-Aware YANG Model         August 2018


8. Contributors


Authors' Addresses

   Young Lee
   Huawei Technologies
   5700 Tennyson Parkway, Suite 600
   Plano, TX 75024
   USA

   Phone: (469) 277-5838
   Email: leeyoung@huawei.com


   Haomian Zheng
   Huawei Technologies

   Email: zhenghaomian@huawei.com





























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